Category-Based Verbal Fluency: #
When asking a patient to come up with as many words as possible based on a category (e.g., animals), this task primarily involves the left temporal lobe, particularly areas associated with semantic memory. The left inferior frontal gyrus (Broca’s area), which is involved in language production, also plays a role in category-based fluency. An example of this type of neuropsychological assessment is the Category Fluency Test.
Letter-Based Verbal Fluency: #
When the instruction is to generate as many words as possible that begin with a specific letter (e.g., “S”), this task relies on frontal lobe structures, particularly the left dorsolateral prefrontal cortex (DLPFC). This type of fluency task is more dependent on executive functions, which involve strategic searching and self-monitoring, functions commonly associated with the prefrontal cortex. An example of this type of neuropsychological assessment is the COWAT.
